Method and electronic control for the analyzation of serum chemistries

ABSTRACT

An electronic control logic system for processing the results of a spectrophotometer analysis of a serum chemistry comprised of a serum and one or more chemical reagents. The spectrophotometer output representing air as a light path and another output representing the test chemistry as a light path are integrated and the air path integrated value allowed to exponentially decay until its value is equal to that of the integrated test chemistry path value. The decay time is converted into a train of digital pulses representative of the optical density of the test chemistry. These pulses are counted and their total stored for comparison with the corresponding optical density of a standard solution. The concentration of the element for which the particular test was designed to detect is known for the standard solution, so the percentage concentration of that element in the test chemistry may be thereby ascertained. Programable variations are provided to enable the evaluation of test results from a kinetic or an end point test. The results of the analysis, together with a test identification number and a patient identification number is selectively applied by a printer control logic section for suitable printing of the data.

United States Patent [191 Durkos et al.

[ June-26, 1973 METHODAND ELECTRONIC CONTROL FOR THE ANALYZATION OF SERUM CHEMISTRIES [75] Inventors: Larry George Durkos, Indianapolis;

Robert Wayne Cole, Zionsville; Jerry William Denney, Carmel, all of Ind.

[73] Assignee: American Monitor Corp., Indianapolis, 1nd.

[22] Filed: Sept. 9, 1971 [21] Appl. No.2 179,135

[52] U.S. Cl..... 235/l51.3, 235/l51.35, 250/435 R, 250/218, 356/81, 356/204 [51] Int. Cl. G06f 15/42 [58] Field of Search 235/151.l3, 151.3, 235/l5l.35; 250/43.5 R, 218; 356139-42, 81-82, 201, 204; 23/230 M, 253 R [56] References Cited UN1TED STATES PATENTS 3,528,749 9/1970 Bowker 356/204 X 3,553,444 1/1971 Tong 235/l51.35 3,633,012 l/l972 Wilhelmson et al. 235/1513 3,609,047 9/1971 Marlow 250/218 X 3,552,863 l/197l I 250/218 X 3,428,796 2/1969 Martens et a1 235/15 1.35 X 3,531,202 9/1970 Wilkinson et al 356/81 3,652,850 3/1972 Briggs 250/43.5 R

REFERENCE VOLTAGE COMPARATOR H.V. SUPPLY Primary ExaminerEugene G. Botz Assistant Examiner.lerry Smith Attorney-Verne A. Trask et a1.

[57] ABSTRACT An electronic control logic system for processing the results of a spectrophotometer analysis of a serum chemistry comprised of a serum and one or more chemical reagents. The spectrophotometer output representing air as a light path and another output representing the test chemistry as a light path are integrated and the air path integrated value allowed to exponentially decay until its value is equal to that of the integrated test chemistry path value. The decay time is converted into a train of digital pulses representative of the optical density of the test chemistry. These pulses are counted and their total stored for comparison with the corresponding optical density of a standard solution. The concentration of the element for which the particular test was designed to detect is known for the standard solution, so the percentage concentration of that element in the test chemistry may be thereby ascertained. Programable variations are provided to enable the evaluation of test results from a kinetic or an end point test. The results of the analysis, together with a test identification number and a patient identification number is selectively applied by a printer control logic section for suitable printing of the data.

10 Claims, 28 Drawing Figures INTEGRATOR FLOW CELL POSITION DETECTOR arm :zTORAoE l 3's COMI'JLEMENT 120 .15 (.()MPllMl.NT m'llvAl H2 152 nENSl lY a v6 .7, g l COUNTER MULTI. CONC. PRINTER m M] g MULT ACCUMULATOR COUNTER LOGIC DIGITAL RATE MOE 2H8 l MULTI STANDARD I24 1 U l '22 30 SWITCH PRINTER I06 9e 94 A. ||6 MASTER GATE 1 MHZ lo 100 KHZ COUNTER CLOCK CLOCK A FIL DETECTOR PAFENTEWunzs 1915.

ON 20mm PAPENIEMunzs x925 SIIEI (IMF-25 PATENIEDJUHZG am I 3.742.196

sum user 2s PATENIED M26 I875 SIEU 0B0? 25 PATENI EU JUN 2 6 I913 SIEH 07 25 w mE PATENIEDJUIIZB ma 3.742.196

am cam 25 FIG.9

PATENIEUJURZB 1915 saw 100! as oov Eu QQVEPO WI! 0.

kwmwmm movmhu PATENTED I975 SIEEI 12K 25 0mm 1P0 kwwm I kwmuma 2% F6 mam Eu Nmn IPO any-PD an 1P0 PAIENIEBJUMes ms mum kwmmmm wnv New

PAIENTEU Jim 2 6 I973 SIIH 150$ 25 OUTPUT OF INVERTER 638 OUT READ CONTROL FE 630 OUT FigJSa SYS RESET 8 a F3 3 1 .F a F 3 6 T a do T .1 8 a n F M P 6 E 6 2 m a m 6 6 5 nl m N a 6 L 5 M w m U m K N l \I 7 0 3 w w 5 PAlENIfimuuze um mNh KOZ

Nmh 05.0 v 

1. An apparatus for determining the concentration of an element in a solution, which comprises analyzation means for determining the light transmittance of a solution and for generating a first analog signal in accordance therewith; said analyzation means being adaptable for determining the light transmittance of a reference substance and for generating a second analog signal in accordance therewith; conversion means for generating a first digital signal from said first and second analog signals, said first digital signal having a first numerical value associated therewith as representative of the optical density of said solution; and calculation means for calculating the percentage concentration of the element in said solution from said first digital signal, said calculation means including generation means for generating and storing a second digital signal having a second numerical value associated therewith representative of the concentration of the element needed in said solution for said first numerical value to equal one; a digital pulse generator for generating a first digital pulse train having pulses occurring at a predeterminable frequency and having first and second outputs; frequency alteration means coupled to said conversion means and said first generator output for altering said frequency in accordance with said first digital signal whereby a second digital pulse train is generated; first counting means coupled to said second generator output for counting the pulses occurring in said first pulse train; second counting means coupled to said frequency alteration means for counting the number of pulses occurring in said second pulse train; detection means for detecting when the number of said first pulse train pulses counted by said first counting means equals said second numerical value and for inhibiting said digital pulse generator when the equation occurs, whereby the number of pulses counted by said second counting means prior to the inhibiting of said generator represents the numerical value of the concentration of the element in said first solution.
 2. An apparatus as claimed in claim 1 wherein said analyzation means includes a spectrophotometer having light sensitive means for generating said first and second analog signals and automatic feedback means for adjusting the supply voltage to said light sensitive means in accordance with changes in the operating characteristics of said spectrophotometer.
 3. An automatic method for determining the percentage concentration of an element in a solution, which comprises the steps of reading the value of the light transmittance of the solution; computing the optical density value of the solution from said light transmittance value; multiplying said optical density value by a scale factor value, said scale factor value being equal to the percentage concentration value of the element which would cause the optical density value to equal one, said multiplying step including generating a first digital pulse train having pulses reoccurring at a predeterminable frequency; counting and storing the number of pulses generated in said first pulse train; generating a second digital pulse train identical to said first pulse train; altering the frequency of said second pulse train in accordance with the optical density of said solution; counting and storing the number of pulses in the thereby altered second pulse train; comparing the stored number of pulses from said first pulse train with saiD scale factor value; and stopping the generating of said first and second pulse trains when the stored number of from said first pulse train equals said scale factor value, whereby the stored number of pulses having occurred in said altered pulse train represents the percentage concentration of the element in the solution; and storing the resulting value of said multiplying step.
 4. An apparatus for determining the concentration of an element in a solution, which comprises analyzation means for determining the value of the optical density of the solution, said analyzation means including optical means for determining the light transmittance of the solution and for generating an analog signal in accordance therewith, conversion means for converting said analog signal to a digital signal representative of the value of the optical density of the solution, and first storage means for storing said digital signal, said analyzation means also being for determining the optical density value of a standard solution having a known concentration value of the element therein, and for determining the optical density value of a blank solution; calculation means for determining a value for a standardizing scale factor representing the concentration of the element in the solution needed for said optical density value to equal one, said calculation means including subtraction means for taking the difference between the optical density value of the standard solution and the optical density value of the blank solution and for storing the difference value thereby obtained in said first storage means, second storage means for storing said known concentration value of said standard solution, and division means for dividing said known concentration by said difference stored in said first storage means to obtain said standardizing scale factor; multiplication means for multiplying said determined optical density by said scale factor value thereby obtaining the value of the concentration of the element in the solution; and display means for presenting said concentration value.
 5. An apparatus for determining the concentration of an element in a solution, which comprises analyzation means for determining the value of the optical density of the solution; calculation means for determining a value for a standardizing scale factor representing the concentration of the element in the solution needed for said optical density value to equal one; multiplication means for multiplying said determined optical density value by said scale factor value thereby obtaining the value of the concentration of the element in the solution, including a digital signal generator having first and second outputs for generating a first digital signal having a predetermined frequency on said first and second outputs, a digital rate multiplier coupled to said first generator output and to said analyzation means for altering said digital frequency on said first output in accordance with said optical density value to generate a second digital signal, first storage means for storing a third digital signal representative of said scale factor value, second storage means coupled to said digital rate multiplier for storing said third digital signal, said first storage means being coupled to said second generator output for receiving said first digital signal, and detection means for detecting when the value of said first digital signal equals the value of said third digital signal stored in said first storage means and for inhibiting said generator concurrently with such detection whereby the value of said second digital signal in said second storage means equals the concentration of the element in the solution.
 6. An apparatus for determining the concentration of an element in a solution, which comprises analyzation means for determining the value of a parameter characteristic of the solution and the value of said parameter for a standard solution having a known concentration of the element therein; calculation means for determininG a value for a standardizing scale factor representing the concentration of the element in the solution needed for said parameter value to equal a predetermined value, said calculation means including arithmetic means for operating on said parameter value for said standard solution in computing said standardizing scale factor value, said arithmetic means also being for operating on said parameter of the solution with said standardizing scale factor to compute the concentration of the element in the solution.
 7. An apparatus as claimed in claim 6, wherein said analyzation means includes means for determining the value of said parameter for a blank solution, and wherein said arithmetic means includes means for operating on said parameter value for said blank solution in addition to said parameter value for said standard solution in computing said standardizing scale factor value.
 8. An apparatus as claimed in claim 6, wherein said analyzation means also being for determining the value of said parameter for a blank solution, and said arithmetic means includes subtraction means for taking the difference between said standard solution parameter value and said blank solution parameter value and for storing the difference value thereby obtained, storage means for storing said known concentration value of said standard solution, and division means for dividing said known concentration value by said difference value stored in said subtraction means to obtain said standardizing scale factor.
 9. An automatic method for determining the percentage concentration of an element in a solution, which comprises the steps of reading the value of a parameter characteristic of the solution; reading the value of said parameter for a standard solution having a known concentration of the element therein; calculating a value for a standardizing scale factor representing the concentration of the element in the solution needed for said parameter of the solution to equal a predetermined value by arithmetically operating on said parameter value for said standard solution; multiplying the calculated scale factor by the value of said parameter for said solution; and storing the result of said multiplying step whereby said result is the value of the percentage concentration of the element in the solution.
 10. A method as claimed in claim 9 including the step of reading the value of said parameter for a blank solution and said calculating step includes the steps of subtracting the standard solution parameter value from the blank solution parameter value, storing the difference value obtained in said calculating step, storing the value of the known concentration of said standard solution and dividing said known concentration value by said difference value to obtain the value for said standardizing scale factor. 